The 23-year-old was part of the Spain squad that won the European Championship in July and has since been linked with a €40m move to the Allianz Arena.

And the former Bayern coach has suggested that the intense scrutiny the player would be under, due to his hefty price tag, will serve to raise expectations on the versatile midfielder.

"Of course, the pressure is immense on such a player. And of course, such a transfer also includes a risk," Hitzfeld stated to DAPD, recalling the issues of Mario Gomez on his big-money move to Bayern.

"How Martinez will deal with these insanely high expectations will be interesting. [There is] No Sheikh behind Bayern, it is hard earned money."

Martinez was not included in the Athletic Bilbao squad for their La Liga season opener, which they lost 5-3 to Real Betis.